In areas where natural precipitation is insufficient, irrigation is necessary for the production of many agricultural crops. Common types of irrigation systems include center pivot systems, wheel-line systems, dragline systems, drip irrigation systems, subterranean irrigation systems, and sprinkler line systems. Each of these systems conventionally includes a water supply pipe. In some irrigations systems the water supply pipe may be formed from multiple pipe sections connected end-to-end by couplers. A plurality of sprinklers is typically mounted at intervals along the water supply pipe.
Water for the irrigation systems may be supplied from a number of sources including, for example, lakes, reservoirs, canals, ditches, rivers, and wells. The water from most of these sources, especially surface water sources, often contains solid debris, such as weeds, grass, sand, sticks, insects, or other solid objects. During operation of the irrigation system, this debris may build up within the water supply pipe and may clog one or more of the sprinklers or even the water supply pipe itself. The debris typically builds up at a second end of the water supply pipe referred to herein as the “distal” end of the water supply pipe, this end being the end that is relatively distant to the water source. The accumulation of debris in the distal end of the water supply pipe may cause sprinklers, especially those proximate the distal end of the water supply pipe, to clog and thereby cease to function properly or at all.
One method of filtering debris in irrigation systems is a simple screen near the inlet end of the pipeline against which the water flow is directed and which prevents larger debris from entering the water supply pipes. Such screens work on a gross level; however, they often allow smaller debris to enter the irrigation system which over time causes clogging of the sprinklers. Furthermore, screens must be monitored to ensure they are promptly cleaned as they become plugged with debris.
Another method for filtering debris, which is commonly used, is an end plug or flush plug placed on the distal end of the water supply pipe. A conventional end plug includes a cap for the end of the water supply pipe that can be manually opened. Once the cap is manually opened, water is sent through the irrigation system to flush any debris in the irrigation system out the distal end of the water supply pipe. A major disadvantage of conventional end plugs is that a person operating the irrigation system alone must travel back and forth between the proximal and distal ends of the water supply pipe to flush the debris out from the water supply pipe. For example, it may be required to travel to the distal end of the water supply pipe, typically a fourth of a mile in length or longer in wheel-line and center pivot systems, to open manually the cap, travel back to the proximal end of the water supply pipe to turn on the water to flush the system, and then travel back to the distal end of the water supply pipe to close manually the cap once the system has been flushed. Furthermore, depending on the type of irrigation system, accessing the end plug may be difficult or awkward. For example, the height of the water supply pipe in a center pivot system can cause the end plug to be difficult to reach. Another disadvantage of conventional end plugs is they provide no way of knowing if the irrigation system needs to be flushed. Typically, the only way to know that a flush is needed is when the sprinklers at the distal end of the water supply pipe stop functioning properly. This requires either regular or constant supervision, or assumption of the risk that a portion of the field will not be watered sufficiently.
Therefore, there is a need in the art for a flushing system that can be used to flush debris from water supply pipes of irrigation systems such as, for example, wheel-line irrigation systems that do not require manual manipulation or operation of the valves to flush the water supply pipes. Additionally there is a need in the art for devices that flush debris out from water supply pipes before the debris clogs any sprinklers along the water supply pipes.